1. Technical Field
The invention relates to cooking appliances, and more particularly, to a food cooking system having a sensor for determining information about the food being cooked.
2. Related Art
Conventional cooking appliances such as ovens, griddles, and waffle irons, use thermostats to control the cooking temperature of the appliance. Thermostats control cooking temperatures by turning heating elements xe2x80x9conxe2x80x9d or xe2x80x9coffxe2x80x9d to maintain a constant temperature at a particular location such as, for example, in the cavity of an oven, at the surface of a griddle, or in or near the food.
Some prior efforts have been made to use thermostats to determine the status of a food item. For example, some prior art waffle irons illuminate a xe2x80x9creadyxe2x80x9d light (or sound a xe2x80x9creadyxe2x80x9d tone), indicating that the waffle being cooked is done. In these prior approaches, the appliance""s fixed temperature thermostat energizes the heating element in response to a cold batter being poured onto the waffle iron. When the thermostat detects that a fixed predetermined temperature has been reached by the heating element, the thermostat deenergizes the heating element, and illuminates the ready light. Operating based on a fixed predetermined temperature (set by the calibration of the thermostat) has certain disadvantages. For instance, under this prior approach, the ready light or tone is triggered at this predetermined temperature, even if the waffle is not yet done, or is over done. Furthermore, since the prior art waffle iron operates only based on a fixed, predetermined temperature, it does not adapt well to particular situations such as differences in waffle recipes that may require a higher or a lower temperature, or to differing food types altogether. In addition, with the prior art waffle irons, at the particular moment when batter is added to the cooking surface, the fixed temperature thermostat may be below the fixed temperature setting, in which case the appliance cannot detect when the food is added. In other words, since the fixed temperature thermostat, under such circumstances, already requires additional heating, the need for additional heating can not change in response to the addition of a food load. This prevents the appliance from having the capability of timing the cooking cycle, and it can only rely on a fixed temperature threshold to indicate when a food might be done. This is a less reliable method of determining the status or doneness of a food item. Thus, there is a need in the cooking art for a cooking system that is able to determine the status of a food item (e.g., when a food item is added to a cooking apparatus or flipped), to automatically determine the beginning of a cooking cycle, or when a food item is done. There is a further need in the art to provide appliances that can control the cooking of various foods based on such determination.
These and other advances in the art are provided by the disclosed system. The system may be embodied in various methods and apparatuses for determining the status of a food item. The system examines the time-temperature curve at either the food item or the cooking medium toward determining, for example, when a user has added a food item to a cooking medium, when a food item has been flipped, or when a food item is done (i.e. finished cooking). In particular, the system may sense a number of temperatures, and/or compare data related to the sensed temperatures with predetermined temperature data (for example, delta setpoints as described in detail below), toward determining the status of the food item. The system may also heat the food item, and may further cause some predetermined action based on the status of the food item.
The system may involve inputting user information corresponding to the food item being cooked. This user information may include what type of food the food item is, or the desired level of doneness of the food item. Also, the system may identify a delta value from a plurality of delta values, determine from the currently determined delta values that a food item has been introduced to the heating medium, and heat the food item for a predetermined period of time. Alternatively, the system may heat the food item until it reaches a predetermined temperature value, regardless of heating time. In addition, the system may also automatically shut off the heating medium in certain circumstances after a predetermined period of time, such as a period of nonuse.
Other systems, methods, features and advantages of the invention will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.